Sound-deadening structure



Feb. 20, 1951 P, G, PElK 2,542,428

SOUND-DEADENING STRUCTURE Filed NOV. l, 1944 FIG. Z

INVENTOR. @fu/L @i ,0f/K

Patented Feb. 20, 1951 SOUND-DEADENING STRUCTURE Paul G. leik, Akron,Ohio, assignor to Thomas L. Fawick, Akron, Ohio Application November 1,1944, Serial No. 561,473

(Cl. 'l2-17) 1 claim. l

This invention relates to sound-deadening, sound-absorbing and soundinsulating structures, and methods of providing the same.

Its chief objects are to provide a layer of material which can be ofsmall thickness and yet be effective for damping the vibration of anunderlying, contacting or adjacent sheet or wail of material; forabsorbing the energy of sound Waves and thus lessening transmission ofsound through the material; and for lessening the reflection of sound.

Another object is to provide a fire-proof structure of this kind.

A further object is to provide a structure and a procedure adapted forconvenient, economical and secure application of the sound-deadeningstructure to surfaces of various contours as well as to surfaces ofplane or other simple form.

Another object is to provide a structure adapted for free fiow of airalong its surface, as in the case of Ventilating tubes or tunnels inships, without such numerous seams or crevices or projections as wouldset up eddy currents in the current of air and thus impede the current.

Of the accompanying drawings:

Fig. 1 is a sectional view of a metal sheet and a composite layer ofmaterials thereon embodying my invention in its preferred form.

Fig. 2 is a similar view of a modification.

Fig. 3 is a sectional view of structure corresponding to that of Fig. 1except that an acoustic surface layer is omitted and the compositesounddeadening layer is applied to concave and convex portions of thesurface of a backing.

Fig. 4 is a sectional view in which the sounddeadening structure isadapted for application to a convex surface with rib elements bent toconform to the convexity of the surface.

Fig. 5 is a face view of a foundation layer such as is employed in thestructure of Figure 4.

Fig. 6 is a sectional view of a modification having provision differentfrom that of Figure 1 for lessening reflection of sound.

Referring to the drawings, and at first to Fig. 1, the structure thereshown comprises a metal member I0, which can be, for example, the flooror wall of an automobile or of a Ventilating tunnel in a ship, which,without the application of a sound deadening structure. would be subjectto being set into sound emitting vibration by the pulsations of a motor,or by gunfire or the like in the case of a vessel of war.

Secured by a suitable adhesive to one of the extensive faces of themember I0, which can be the inner surface in the case of an automobile 2floor or body, or can be either the inner or outer surface in someinstalations, is a layer of vulcanized soft-rubber or the like II,preferably of low grade, inexpensive, highly pigmented rubber havinghigh hysteresis loss in being deformed.

This layer of rubber or the like is formed, on its face farthest fromthe member I0, with undercut anchorage recesses for receiving portionsof and thus anchoring a layer I2 of a setting composition such asfine-aggregate concrete, the anchorage recesses in this embodiment beingdefined by a series of parallel, dove-tail ribs I3, I3 formed as anintegral part of the layer II of rubber or the like.

The layer I2 of setting material preferably is of Haydite concrete, thesmall, aggregate-particles being of a material known as Haydite, formedof a mixture of clay and shale burned almost to fusion and later groundand sifted.

A characteristic of these particles is understood to be that in theburning process the destruction of organic matter leaves small, closedcells in the material, but with the ce.ls broken open at the surface ofeach particle in the grinding operation, so that the Portland cementacquires firm anchorage to them.

Advantages of the Haydite concrete are that it is very light, yetstrong, adapted to withstand vibration without deterioration, and hasapparently high sounddeadening effect, especiallyv when combined withthe rubber-like layer.

The concrete layer can be formed on the rubber layer by molding itagainst the rubber before the rubber is applied to the member I0. Foreconomy, the rubber layer preferably is formed by extrusion andvu-canized in open heat and the concrete preferably is troweled onto itafter the rubber layer has been secured to the member For the concretelayer of this embodiment of Fig.,1, the mix preferably consists of aboutone part by measure of the Haydite particles to one part of mortarcement.

After the concrete layer has been applied but before it has set anacoustic layer I4, of glassfiber or other felt or the like, can be stuckto it to provide against echoing or reiiecting of sound from that sideof the structure.

In tests the structure shows strikingly high sound-deadening effects,which mayv be due in part to the fact that the three layers I0, II andI2 individually have widely different natural rates of vibration.

In the modification shown in Fig. 2 a layer Ila amas of fabric isadhered to the member i8 and the layer lla of setting material ls ofplaster of Paris or other material adapted to adhere to the face of thefabric in the process of setting.

The structure shown in Fig. 3 corresponds to that shown in Fig. 1 exceptthat the acoustic" layer I4 of Fig. 1 is omitted and the figure showsthe adaptability of the structure for a wall or door member of convex orconcave contour.

In some installations the rubber layer, lib (Pigs. 4 and 5) may berequired to be applied with its ribs curved in the direction of theirown lengths, and to make them more bendable the ribs can be cross-cut atintervals, as at I3c, llc. Pigs. 4 and 5, down to, but not through, theweb that connects them.

y 'Ihe structure shown in Fig. 6 corresponds to that shown in Fig. 1except that instead of the acoustic layer Il of the glass-liber felt orthe like a non-sound-reilectlng surface is provided by preforming, as bymolding, and then setting in the surface of the 1 to 1 Haydlte concreteI2, a multiplicity of tiles I5, I5 formed of about 10 to l Hayditeconcrete, the smallI amount of Portland cement requiring the preformingof the tiles as by molding and providing a porosity having the eiIect ofreducing sound-redaction. At the same time the tiles also have thefunction of adding their eect to that of the underlying layer fordamping vibration of the structural member l0.

Further modifications are possible within the scope of the appendedclaim, which is not wholly limited to a layer of setting material havinggreat rigidity or stiffness against bending.

In the appended claim the word wall is intended to be inclusive ofceilings.

I claim:

A sound-deadening, habitation-defining, housing structure comprising asheet of material having substantially the resilient deformability ofvulcanized soft-rubber and formed with projections on one of itsextensive faces and a set layer of an initially ilowable settingmaterial formed against said sheet and having the proiections embeddedtherein and supportingly interlocked therewith. and means supporting thesaid structure as a wall element of a building, the deilned sheet ofmaterial being supported by the definedl supporting means and thedefined set layer being supported by the denned sheet of material.

PAUL G. PEIK.

REFERENCES Cm The following references are of record in the ille of thispatent:

UNITED STATES PATENTE Number Name Date 906,025 Howe Dec. 8, 19081,115,266 Wiltse Oct. 27, 1914 1,255,878 Hayde Feb. 12, 1918 1,383,344Shaw July 5, 1921 1,494,926 Makowski May 20, 1924 1,707,255 Darrow Apr.2, 1929 1,728,991 Draullette Sept. 24, 1929 1,870,101 Davey Aug. 2, 19321,906,637 Bchulke May 2, 1933 1,950,420 Btitt Mar. 13, 1934 1,955,443Spailord Apr. 17, 1934 2,114,388 Killion Apr. 19, 1938 2,139,851 RobertsDec. 13, 1938 2,168,949 Bentz et al. Aug. 8, 1939 2.323.936 Roberts July13, 1943 FOREIGN PATENTS Number Country Date 456,189 France Aug. 19,1913 68,612 Switzerland Apr. 22, 1914 300,138 Great Britain Oct. 3, 1929171,632 Switzerland Nov. 18, 1934

